Is it possible to save animation as frame by frame to edit?
Blender does have the ability to render to individual frames (PNG format is popular) and this is the preferred workflow.



I like to increase the compression to 100%, and if you aren't rendering frames with transparency, then use RGB instead of RGBA.  And uncheck the Overwrite box.  If you decide you need to throw away the previously rendered frames (because you updated the animation or whatever) you can delete them using your file explorer or bash.

As you have calculated this can result numerous images, which are usually each pretty large.

When you say you intend to "edit" the results of blender's rendering, you are being pretty vague, and depending upon the nature of the alterations you want to perform, your workflow can vary drastically.